In the Spring of 1943, Squadron Leader Roger Bushell RAF conceived a plan for a major escape from the camp, which occurred the night of March 24-25, 1944

Bushell was held in the North Compound where British airmen were housed. He was in command of the Escape Committee and channeled the effort into probing for weaknesses and looking for opportunities. Falling back on his legal background to represent his scheme, Bushell called a meeting of the Escape Committee and not only shocked those present with its scope, but injected into every man a passionate determination to put their every energy into the escape. He declared,

"Everyone here in this room is living on borrowed time. By rights we should all be dead! The only reason that God allowed us this extra ration of life is so we can make life hell for the Hun... In North Compound we are concentrating our efforts on completing and escaping through one master tunnel. No private-enterprise tunnels allowed. Three bloody deep, bloody long tunnels will be dug - Tom, Dick, and Harry. One will succeed!"

The simultaneous digging of these tunnels would become an advantage if any one of them was discovered by the Germans, because the guards would scarcely imagine that another two could be well underway. The most radical aspect of the plan was not merely the scale of the construction, but the sheer number of men that Bushell intended to pass through these tunnels. Previous attempts had involved the escape of anything up to a dozen or twenty men, but Bushell was proposing to get in excess of 200 out, all of whom would be wearing civilian clothes and possessing a complete range of forged papers and escape equipment. It was an unprecedented undertaking and would require unparalleled organization. As the mastermind of the Great Escape, Roger Bushell inherited the codename of "Big X".[17] The tunnel "Tom" began in a darkened corner of a hall in one of the buildings. "Dick"'s entrance was carefully hidden in a drain sump in one of the washrooms. The entrance to "Harry" was hidden under a stove.[18] More than 600 prisoners were involved in their construction.[8]http://en.wikipedia.org/wiki/Stalag_Luft_III
Taken from wikipediahttp://en.wikipedia.org/wiki/Stalag_Luft_III